Positive action cam track for automatic guns with rotatable cartridge drum



E- s. WASSE 2 786 VE ACTION CAM TRACK 0 AUTOMATIC ,394 s WITH ROTATABLE CARTRI E DRUM 2 Sheets-Sheet l GUN March 26, 1957 POSIT Filed Dec. 17, 1954 March 26, 1957 E. s. WASSEL 2,786,394

POSITIVE ACTION CAM TRACK FOR AUTOMATIC GUNS WITH ROTATABLE CARTRIDGE DRUM Filed Dec. 17, 1954 2 Sheets-Sheet 2 IN V EN TOR.

Eugene. E1- Wuasal BY WWJMW 4 ATTORNEYS POSITIVE ACTION CAM TRACK FOR AUTO- MATIC GUNS WITH ROTATABLE CARTRIDGE DRUM Eugene S. Wassel, Cicero, 111., assignor, by mesne assignments, to the United States of America as represented by the Secretary of the Army Application December 17, 1954, Serial No. 476,097

Claims. (Cl. 89-155) My invention relates to an automatic weapon with a rotatable cartridge drum and an actuator for revolving the drum, and more particularly to a cam device for guiding the actuator.

Such a weapon usually comprises a recoil unit for supporting the drum slidable in a recoil cycle on a receiver responsive to operation of the weapon. The recoil unit includes a barrel and the drum includes cartridge chambers and corresponding index rollers. An actuator in the receiver is biased to a battery position for engagment with one of the rollers to retain the chamber corresponding thereto in a firing position in axial alignment with the barrel and slidably disposed for rearward and forward stroke reciprocation responsive to discharge of cartridges chambered in the firing position to successively rotate the chambers to the firing position. The actuator includes a pivoted tongue with a projecting follower pin engageable with a receiver cam for roller engagement to sequentially convey the chambers to the firing position responsive to the discharge.

This arrangement of components has been found to be unsatisfactory since variations such as the allowable differences in charge of cartridges cause substantial differences in period of the strokes of both the recoil unit and the actuator, and these dilferences are required to be compensated in a tongue cam fixed in the receiver. Several forms of resilient tongue cams have been cleveloped but the follower pins have been deformed in all of them to cause malfunctions of the weapon.

It is, therefore, an object of my invention to provide a revolver-type automatic weapon having an actuator with a pivoted tongue with a cam having rigid guide surfaces for engagement therewith for accurate control of rotation of the cartridge drum in the weapon.

Another object of my invention is to provide such a tongue cam disposed for reciprocation responsive to the recoil and counter-recoil of the weapon.

A further object of my invention is to provide a tongue cam for operation in unison with the recoil unit.

Other aims and objects of my invention will appear from the following explanation thereof.

In carrying out my invention, a weapon similar to the one described above is provided with a tongue cam having rigid guide surfaces included in a carriage slidable in the receiver. The carriage is secured to the recoil unit for unitary operation therewith.

For a more complete understanding of my invention, reference is made to the following description and the accompanying drawings in which:

Fig. l is a partly sectioned elevational view of a revolver-type automatic weapon incorporating my invention;

Fig. 2 is a view along line 2-2 of Fig. 1;

Fig. 3 is a view along line 33 of Fig. 2; and

Fig. 4 is a view along line 44 of Fig. 1.

Accordingly, a revolver-type automatic weapon 12 includes a receiver 14 and a unit 16 slidable in recoil therenited States Patent 0 2,786,394 Patented Mar. 26, 1957 corresponding roller is shown at 24 and a cartridge 26.

is disposed in chamber 22.

An actuator 28 for controlling rotation of drum 20 is biased to a battery position by springs 30 in engagement. with receiver 14 and is slidably disposed on the receiver.

for rearward and forward stroke operation responsive to discharge of cartridges chambered in the firing position. The actuator includes a track 32 for engagement with the rollers, including a straight portion 34 for engaging one of the rollers to retain the corresponding chamber in the firing position when actuator 28 is in battery position.

A pair of oppositely curved portions 36 and 38 of roller track 32 communicate with straight portion 34. The connections between the curved portions and the straight portion are completed for respective engagement with adjacent rollers during the rearward and forward strokes of actuator 28 to accelerate and decelerate rotation of drum 20 by a tongue 40 pivoted at 42. Tongue 40 includes a projecting follower pin 44 with a tip 46 biased by a spring 47.

A carriage 48 slidable on receiver 14 is provided with clamps 51] for engaging a T-section 52 of recoil unit 16 for operation therewith and a cam 54 having rigid walls for engaging follower pin 44. The floor of cam 54 includes recesses 56 and 58 for rearward and forward stroke engagement of tip 46 respectively to retain follower pin 44 in engagement with the walls of the cam and to control the sense of progress of follower pin 44 in cam 54. Recesses 56 and 58 respectively include ramped sections at the rearward and forward ends thereof to permit tip 46 to leave the recesses.

Cam 54 includes curved portions 60 and 62 for switching tongue 40 respectively at the ends of the rearward and forward strokes of actuator 28 to permit tongue 40 to complete the connection of portions 36 and 38 with straight portion 34.

Since carriage 48 is secured to recoil unit 16 in my invention the variations in charge of the cartridges affect the axial movement of recoil unit 16, carriage 48 and actuator 28 equally, and the rigid surfaces of cam 54 may be accurately formed to control rotation of tongue 40.

Although a particular embodiment of the invention has been described in detail herein, it is evident that many variations may be devised within the spirit and scope thereof and the following claims are intended to include such variations.

1 claim:

1. An automatic weapon comprising a recoil unit hav ing a rotatable cartridge drum with radial index rollers, an actuator slidable in rearward and forward strokes with respect to said recoil unit for engagement with said index rollers responsive to discharge of said weapon, a tongue pivoted on said actuator between positions for respective rotational acceleration and deceleration of said drum during said strokes including a projecting follower pin, and a carriage including a rigid cam for engagement with said follower pin, said carriage being secured to said recoil unit accurately to retain said tongue in said positions and to switch said tongue to and from said deceleration position during said rearward and forward strokes respectively.

2. In an automatic weapon including a recoil unit, a drum provided with cartridge chambers and index rollers therefor, and disposed for rotation of the chambers to a firing station for discharge of cartridges therein, an actuator disposed for reciprocation with respect to the recoil unit for acceleration and deceleration of the drum to successively convey the chambers to the firing position responsive to the discharge, and a tongue for engagement with the rollers pivoted on the actuator between positions respectively corresponding to the acceleration and decelera'tion and provided with a projecting follower pin having a spring-biased tip, a switch device comprising a carriage secured to the recoil unit and provided with a cam for engagement with the follower pin to retain the tongue in the respective positions and to displace the tongue therebetween responsive to the discharge.

3. A switch device as described in claim 2 with said cam provided with rigid surfaces for engagement with the follower pin.

4. A switch device as described in claim 2 with said 4 cam provided with rigid surfaces and grooves for respective engagement with the follower pin and the springbiased tip to selectively retain the switch tongue in said acceleration and deceleration positions, said rigid surfaces having curved portions for engagement with the follower pin to direct the switch tongue between said positions. I

5. A switch device as described in claim 4 with said grooves provided with bottoms ramped at a pair of corresponding ends thereof for progress of the follower pin in a single sense in said cam.

1,040,335 France May 20, 1953 

